Comparison of potassium hydroxide digestion and a modified Kato technique for the semi-quantitative estimation of Schistosoma mansoni eggs in faeces.

A simple method for the semi-quantitative estimation of eggs of Schistosoma mansoni in stools, based on digestion of faeces in 4% potassium hydroxide (KOH), is described. The relative performance of KOH digestion and a modified Kato method showed that the former was more sensitive and that the KOH/Kato ratio for the geometric mean number of eggs per gram, in stools positive by both methods, was 3.51.